Considering how badly I've had crossbreeding regular TWBs go
Are you having problems breeding two TWB genome breeds together, or breeding TWBs with other genome types like CFFs, CFEs or 2017s? The latter is indeed difficult as the changes are spread throughout the entire genome. If it's the former then that really shouldn't be happening...
You could always slap some Draconian sprites on a Basilisk genome
Swapping sprites onto different genomes is always a valid way of breeding for aesthetics.
Though having said that, I would love to see the Draconians made truly cold blooded (as they were meant to be, but as with all old genomes couldn't actually sense air temperature) and updated for the CFE/CFF brain type. I would do so myself but don't want to step on any toes.